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Divisibility. Rules!. What is Divisibility?. Divisibility means that : after dividing, there will be no remainders. 30. 3. 1. 2. 6 2. 2. 6 1. 6. 6. 1. 2. 2. 0. 0. No reminders. 1. Reminders. Use your calculator. ÷ 4 = 542 ÷ 2 = 59 ÷ 3= 620 ÷ 5 = 75 ÷ 4 =
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Divisibility Rules!
What is Divisibility? Divisibility means that : after dividing, there will be no remainders. 30 3 1 2 6 2 2 6 1 6 6 1 2 2 0 0 No reminders 1 Reminders
Use your calculator ÷ 4 = 542 ÷ 2 = 59 ÷ 3= 620 ÷ 5 = 75 ÷ 4 = 12040 ÷ 10 =
Can you tell by just looking at this number if it is divisible by 2? by 5? by 10? by 3 ? by 9? By 6? The divisibility rules can help you! 356,821
Divisibility rules help you learn shortcuts to tell when a number can be divided by another number without any remainders.
A number is divisible by 2 if the number is even. 18 ÷ 2 = 9 22 ÷ 2 = 11 (18 and 22: Notice that both of these dividends are even.) 21 ÷ 2 = 10 R1 (21: not an even number.) Divisibility by 2
Are these numbers divisible by 2? On your whiteboard 127 24 4678 11 325 20
Divisibility by 5 • A number is divisible by 5 if it ends in 0 or 5. 25 ÷ 5 = 5 23 ÷ 5 = 4 R3
Are these numbers divisible by 5? • 328 • 215 • 4670 • 21 • 84 • 9 • 185470 (Units are not 0 or 5 (Units are not 0 or 5 (Units are not 0 or 5 (Units are not 0 or 5
A number is divisible by 10 if it ends in 0. 30 ÷ 10 = 3 340 ÷ 10 = 34 67 ÷ 10 = 6 R7 784 ÷ 10 =78 R4 Divisibility by
Divisibility by 3 • A number is divisible by 3 if the sum of the digits is divisible by 3. Is the number 135 divisible by 3? Add the digits: 1 + 3 + 5 = 9 Yes, 135 is divisible by 3 because the sum of the digits is divisible by 3.
Are these numbers divisible by 3? • 328 • 216 • 4680 • 21 • 85 • 19 • 65410
A number is divisible by 6 if it is divisible by both 2 and 3. Is 42 divisible by 6? Think: Is 42 divisible by 2? Is 42 divisible by 3? Divisibility by 6 Is 51 divisible by 6?
Are these numbers divisible by 6? • 32 • 21 • 48 • 36 • 85 • 18 • 65410
A number is divisible by 9 if the sum of its digits is divisible by 9. 369 is divisible by 9 because 3 + 6 + 9 =18 1 + 8 = 9 and 9 is divisible by 9. Divisibility by 9
Are these numbers divisible by 9? • 42 • 207 • 61 • 1288 • 33 • 24 • 65410
Divisibility by 25 Divisibility by 100 A number is divisible by 25 if the last two digits are 25 , 75 , 50 , 00 A number is divisible by 100 if the last two digits are 00 Examples Examples • 1420 • 1420 ÷ 25 =56.8 • 600 • 600 ÷ 25 = 24 • 6500 • 6500÷ 100=65 • 610 • 610÷ 100= 6.1
Divisibility by 4 A number is divisible by 4 if the last two digits are divisible by 4. Examples: 1320 20 ÷ 4 = 5 672 72 ÷ 4 = 18
Now You Try: Which number IS NOT divisible by 4? 564 4101 188